Patent US4624547A successfully refreshed from Google Patents.
US4624547A
Expired / Lapsed
US
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Image forming apparatus
Assignee: Canon Inc
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Filing: 1984-06-22
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Granted: 1986-11-25
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Expires: 2004-06-22
Abstract
Abstract There is disclosed an image forming apparatus capable of image formation under optimum image forming conditions in response to the detected image density. The image forming apparatus has image forming unit for forming an image corresponding to an original on a recording material, detector for detecting the image density of the original, and controller for controlling the operable condition of said image forming unit to regulate the copy density in response to the image density detected by said detector said controller includes memory storing control data for the operable condition of said image forming unit in response to the detected image density, and is adapted to make an access to said memory in response to the detection signal of said detector and to control said operable condition according to control data obtained by said access.
Inventors
- 👤 Makoto Endo
- 👤 Satoshi Ono
- 👤 Takao Toda
- 👤 Kazuo Kashiwagi
- 👤 Masaaki Yanagi
- 👤 Yoshihiro Saito
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 10:29
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/50; G03G15/5025
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
150 words
An image forming apparatus comprising: image forming means for forming an image corresponding to an original on a recording material; detecting means for continuously detecting the image density of the original, said detecting means detecting the maximum and minimum values of the image density; and control means for controlling an operable condition of said image forming means to regulate the copy density in response to the maximum and minimum values of the image density detected by said detecting means; wherein said control means comprises memory means for storing a plurality of control data corresponding to the maximum and minimum values of the image density, and wherein said control means obtains access data in response to the maximum and minimum values from said detecting means, accesses said memory means in response to the access data, and controls said operable condition in response to said control data obtained by said access data.
Claim 2
Dependent Claim
150 words
An image forming apparatus comprising: image forming means for forming an image corresponding to an original on a recording material; detecting means for continuously detecting the image density of the original, said detecting means detecting the maximum and minimum values of the image density; and control means for controlling an operable condition of said image forming means to regulate the copy density in response to the maximum and minimum values of the image density detected by said detecting means; wherein said control means comprises memory means for storing a plurality of control data corresponding to the maximum and minimum values of the image density, and wherein said control means obtains access data in response to the maximum and minimum values from said detecting means, accesses said memory means in response to the access data, and controls said operable condition in response to said control data obtained by said access data.
Claim 3
Dependent Claim
36 words
An image forming apparatus according to claim 1, wherein said control means provides an operation mode for accessing said memory means in accordance with the difference between the maximum and minimum values of said image density.
Claim 4
Dependent Claim
45 words
An image forming apparatus according to claim 2, wherein said memory means comprises a first memory unit storing control data corresponding to said maximum or minimum value, and a second memory unit storing control data corresponding to the difference of said maximum and minimum values.
Claim 5
Dependent Claim
44 words
An image forming apparatus according to claim 2, wherein said image forming means comprises exposure means for original exposure, and said control means is adapted to control the amount of exposure of said exposure means in response to the output of said detecting means.
Claim 6
Dependent Claim
15 words
An image forming apparatus according to claim 4, wherein said original is a film original.
Claim 7
Dependent Claim
54 words
An image forming apparatus according to claim 5, wherein said control means is adapted, in case said film original is a negative image, to control said exposure by means of control data corresponding to the minimum value of said image density and control data corresponding to the difference between the maximum and minimum values.
Claim 8
Dependent Claim
54 words
An image forming apparatus according to claim 5, wherein said control means is adapted, in case said film original is a positive image, to control said exposure by means of control data corresponding to the maximum value of said image density and control data corresponding to the difference between the maximum and minimum values.
Claim 9
Dependent Claim
146 words
an image forming apparatus comprising: image forming means for forming an image corresponding to an original on a recording material, wherein said image forming means comprises exposure means for original exposure; detecting means for detecting the image density of the original, said detecting means detecting the maximum and minimum values of said image density of the original; and control means for controlling said exposure means to regulate the copy density in response to the maximum and minimum values of said image density of the original detected by said detecting means, wherein said control means comprises timer means for performing a timer operation in response to the maximum or minimum value of said image density so as to control said exposure means, wherein a setting mode of the timer operation is adjusted in response to a difference between the maximum and minimum values of said image density.
Claim 10
Dependent Claim
146 words
an image forming apparatus comprising: image forming means for forming an image corresponding to an original on a recording material, wherein said image forming means comprises exposure means for original exposure; detecting means for detecting the image density of the original, said detecting means detecting the maximum and minimum values of said image density of the original; and control means for controlling said exposure means to regulate the copy density in response to the maximum and minimum values of said image density of the original detected by said detecting means, wherein said control means comprises timer means for performing a timer operation in response to the maximum or minimum value of said image density so as to control said exposure means, wherein a setting mode of the timer operation is adjusted in response to a difference between the maximum and minimum values of said image density.
Claim 11
Dependent Claim
38 words
An image forming apparatus according to claim 8, wherein said exposure means receives the supply of an AC voltage, and said timer means is adapted to effect the timer function from a zero-crossing point of said AC voltage.
Claim 12
Dependent Claim
47 words
An image forming apparatus according to claim 9, wherein said control means is adapted to turn off power supply to said exposure means during the timer function of said timer means and to turn on power supply to said exposure means upon expiration of said timer function.
Claim 13
Dependent Claim
38 words
An image forming apparatus according to claim 9, wherein the operation time of said timer means is a time corresponding to the maximum or minimum value of said image density and to a frequency of said AC voltage.
Claim 14
Dependent Claim
108 words
An image forming apparatus comprising: image forming means for forming an image corresponding to an original on a recording material; detecting means for detecting the image density of the original; amplifying means for amplifying the output of said detecting means with different gains in the course of detection of the image density by said detecting means; and control means for controlling said image forming means to regulate the copy density in response to the output of said amplifying means, wherein said amplifying means comprises two amplifying circuits of mutually different gains, which respectively release data corresponding to the measurements of maximum and minimum values of said image density.
Claim 15
Dependent Claim
108 words
An image forming apparatus comprising: image forming means for forming an image corresponding to an original on a recording material; detecting means for detecting the image density of the original; amplifying means for amplifying the output of said detecting means with different gains in the course of detection of the image density by said detecting means; and control means for controlling said image forming means to regulate the copy density in response to the output of said amplifying means, wherein said amplifying means comprises two amplifying circuits of mutually different gains, which respectively release data corresponding to the measurements of maximum and minimum values of said image density.
Claim 16
Dependent Claim
31 words
An image forming apparatus according to claim 12 wherein said control means comprises input means for entering, by switching an a time-sharing basis, the output signals from said two amplifying circuits.
Claim 17
Dependent Claim
15 words
An image forming apparatus according to claim 13, wherein said input means comprises a multiplexer.
Claim 18
Dependent Claim
27 words
An image forming apparatus according to claim 13, wherein said input means sample hold means for holding samples of the output signals from said two amplifying circuits.
Claim 19
Dependent Claim
94 words
An image forming apparatus comprising: image forming means for forming an image corresponding to an original on a recording material; detecting means for detecting the image density of the original; amplifying means for amplifying the output of said detecting means with different gains in the course of detection of the image density by said detecting means; and control means for controlling said image forming means to regulate the copy density in response to the output of said amplifying means, wherein said amplifying means comprises an amplifier and switching means for varying the gain thereof.
Claim 20
Dependent Claim
94 words
An image forming apparatus comprising: image forming means for forming an image corresponding to an original on a recording material; detecting means for detecting the image density of the original; amplifying means for amplifying the output of said detecting means with different gains in the course of detection of the image density by said detecting means; and control means for controlling said image forming means to regulate the copy density in response to the output of said amplifying means, wherein said amplifying means comprises an amplifier and switching means for varying the gain thereof.
Claim 21
Dependent Claim
26 words
An image forming apparatus according to claim 16, wherein said switching means is adapted to switch said gain by selecting a feedback circuit of said amplifier.
Claim 22
Dependent Claim
35 words
An image forming apparatus according to claim 17, wherein said feedback circuit comprises plural resistors connected in parallel between the input and output of said amplifier, and switching means for selecting one of said resistors.
Claim 23
Dependent Claim
22 words
An image forming apparatus according to claim 18, wherein said control means is adapted to switch said switching means on time-sharing basis.
Claim 24
Dependent Claim
179 words
An image forming apparatus comprising: image forming means for forming an image corresponding to an original on a recording material; detecting means for continuously detecting the image density of the original, said detecting means detecting the maximum and minimum values of said image density of the original; and control means for controlling an operable condition of said image forming means so as to regulate the copy density in response to the maximum and minimum values of said image density detected by said detecting means, wherein said control means comprises first memory means for storing a plurality of first control data corresponding to the maximum or minimum value of said image density, and second memory means for storing a plurality of second control data for controlling said operable condition means, said first memory means being accessed in response to the maximum and minimum values from said detecting means and said second memory means being accessed in response to the accessed first control data, and wherein said control means controls said operable condition in response to the accessed second control data.
Claim 25
Dependent Claim
179 words
An image forming apparatus comprising: image forming means for forming an image corresponding to an original on a recording material; detecting means for continuously detecting the image density of the original, said detecting means detecting the maximum and minimum values of said image density of the original; and control means for controlling an operable condition of said image forming means so as to regulate the copy density in response to the maximum and minimum values of said image density detected by said detecting means, wherein said control means comprises first memory means for storing a plurality of first control data corresponding to the maximum or minimum value of said image density, and second memory means for storing a plurality of second control data for controlling said operable condition means, said first memory means being accessed in response to the maximum and minimum values from said detecting means and said second memory means being accessed in response to the accessed first control data, and wherein said control means controls said operable condition in response to the accessed second control data.
Claim 26
Dependent Claim
54 words
An image forming apparatus according to claim 20, wherein said first memory means has a plurality of memory tables, and said control means selects said memory table in response to the difference between the maximum and minimum values of said image density so as to change an access mode for said first memory means.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-11-24 | 1990-05-26 | 1990-11-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-11-24 | 1994-05-26 | 1994-11-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-11-24 | 1998-05-26 | 1998-11-25 | $7700.00 | Window Closed / Lapsed |